I have A727TF (SB) hooked to 1st Gen 392 Hemi, useing Hot Heads adapter. The tranny/carb linkage is Lokar, connected to 2 500cfm edelbrock carbs. My kickdown does not kickdown. Keeping in mind, I am not a mechanic, just a tinkerer. Can someone simpify the adjustment for me. It's a 48 DeSoto hot rod, shifter on the column.

THANK YOU,
Jack

The most likely cause is a mismatch in the range of motion between the throttle lever on the trans and the cable. To check, disconnect the cable at the trans throttle lever and then carefully measure the total movement to go from front to back (no throttle pressure to full throttle pressure). Then measure to total movement at the attaching point on the carb. They must be equal. If not they do sell adapters for the carb linkage, or you can find a different throttle lever for the trans, or you can do some fab and redrilling of mounting holes. Once the total movement is matched, adjust it so the there is no throttle pressure (movement at idle) but it should immediately start to move the linkage as soon as you start to open the throttle. Get this correct or you will cause damage to your trans.

Never kicks down even at around 30 mph?

At light throttle what are your shift points from 1-2 and 2-3?

What HemiSportFury said. Also, be sure that WOT at the pedal is WOT under the hood. IOW, have somebody sit in the car and floor the throttle then, from under the hood, push back on the carbs to make sure they are wide open. With the carbs wide open the transmission lever should be near full back.

Thanks everyone for the advice. Sorry so long, been in the garage all day, every day this week working on the Odd rOd (48 DeSoto). Have not even gotten around to working on the kickdown issue. Plan to start on that 1st of next week. Anyone else with "simple" solutions (I ain't no mechanic), will be greatly appreciated. Stay safe, keep 6ft apart (tough to do when having sex), and don't wear a mask unless you are planning to rob a convenience store.

Jack

1ST to 2ND, about 10MPH........2ND to 3rd, between 15-20 MPH

Getting the throttle kickdown linkage adjusted properly IS the simple solution. If that doesn't correct the problem you are going inside the transmission to at least work on the valve body or governor. Good luck. It's not that difficult to check or correct.

You have all the info you need, the problem is the Lokar..........it's poorly designed AKA junk.

Shifting that early sounds like you are not making enough throttle pressure. Lever is too far forward at any given point.
Like said earlier- check at WOT and see if the lever is almost all the way back.

Lastly, what axle ratio are you running? A high numerical axle ratio makes it even harder to get a downshift at “normal” speeds.

3:23

Can not argue with you on the Lokar/AHA Junk. Where would I start finding "original" type linkage with my engine/tranny combo?

You had the talent to mate an old engine to a newer trans, just do what somewhat mentioned - calculate total travel at the carb then modify the throttle pressure lever to get you what you need at the trans.

I found a linkage made by Offenhauser. Do you think it may be better than the Lokar? In the picture looks much hefitier and straight forward?

do you have a link or picture for the offenhauser linkage ?

Because the installation is a hybrid, the cable is probably the best way to go. Follow the instructions above regarding matching the carb and trans lever travel and you'll be fine.

The Boucillon kit works well, exact copy of factory system, but expensive.

https://www.bouchillonperformance.com/meta-product-kickdown-cable-kit

I put a bouchillon kick down on my Powerwagon and it works great. I think I had to drill a different hole in the kickdown lever to get the correct travel though. I imagine different carburetors and throttle bodies could have different travel lengths.

I really like it. Have added to my cart, but not pulled the trigger yet. I have contacted them with couple of questions, especially the bracket that would be required with my carb comb. THANK YOU.

Jack

I agree have it on my car and no issues

No, sorry. I found it on the Hemi Hot Heads site.